HR: 0800h
AN: SA31A-15    [Abstracts]
TI: Two-Station Height Measurements of Mesospheric Bores at Equatorial latitudes
AU: * Taylor, M J
EM: mtaylor@cc.usu.edu
AF: Center for Atmospheric and Space Sciences, Utah State University, 4405 Old Main Hill, SER Bldg., Logan, UT 84322-4405, United States
AU: Medeiros, A F
EM: afragoso@df.ufcg.edu.br
AF: Universidade Federal de Campina Grande, Rua Aprígio Veloso, 882 - Bodocongó, Campina Grande, PB 58109-970, Brazil
AU: Taylor, V
EM: vtaylor@cc.usu.edu
AF: Center for Atmospheric and Space Sciences, Utah State University, 4405 Old Main Hill, SER Bldg., Logan, UT 84322-4405, United States
AU: Buriti, R A
EM: rburiti@df.ufcg.edu.br
AF: Universidade Federal de Campina Grande, Rua Aprígio Veloso, 882 - Bodocongó, Campina Grande, PB 58109-970, Brazil
AU: Takahashi, H
EM: hisaotak@laser.inpe.br
AF: Instituto Nacional de Pesquisas Espaciais, Av dos Astronautas, 1.758 Jd. Granja, São José dos Campos, SP 12227-010, Brazil
AB: Since their discovery in the early 1990s mesospheric bores have become a topic of considerable interest. These are most unusual gravity wave events that are characterized in the nightglow emissions by a sharp leading front usually followed by a coherent train of waves that grow in number with time. Recent coordinated imaging and Na lidar wind/ temperature measurements have established the coexistence of mesospheric temperature inversion layers which act as a duct supporting the horizontal propagation of the bores. Depending on the altitude of the thermal duct, the optical signatures of the bore induced in the near infrared OH Meinel bands (peak altitude ~87 km), O₂ (0,1) band (altitude ~94 km), and the OI (557.7 nm) line (altitude ~96 km) will be quite different. However, to date there have been no direct height measurements of such bore events. This poster presents novel two-station measurements of mesospheric bores imaged near simultaneously in the OH emission at equatorial latitudes during 2006--2007. The observations were made from north-eastern Brazil using two all-sky CCD cameras, one located at São João do Cariri (7°S, 36°W) and operated by the Federal University of Campina Grande. The second camera, from Utah State University, was located at Monteiro (7.9°S, 37.1°W) giving a site separation of ~85 km. At least four bore events have been identified in both data sets. Their signatures are faint but sufficient to permit an initial investigation of their height ranges.
DE: 0310 Airglow and aurora
DE: 3332 Mesospheric dynamics
DE: 3334 Middle atmosphere dynamics (0341, 0342)
DE: 3384 Acoustic-gravity waves
SC: SPA-Aeronomy [SA]
MN: 2007 Joint Assembly